The refuse collection business is one of the most rapidly growing areas of the economy. There is a correlation between the total population and the amount of refuse disposed of by the population. In addition, there is a correlation between the industrial level of a country and the amount of refuse disposed of by its population. As a country becomes more industrialized, its citizens become more literate and more affluent. These changes may produce a relatively large increase in the amount of disposable refuse, both in the form of written material such as newspapers, magazines, etc., and also in the form of disposable items such as bottles and containers of various types.
Several types of refuse collection vehicles are commonly used in collecting refuse. Rear loading vehicles are generally used in picking up refuse from homes with the refuse in a trash can or in a plastic bag which is dumped into a hopper positioned at the rear of the vehicle.
Front end loading vehicles, or front end loaders, are commonly used in picking up refuse from locations such as schools, factories, office buildings, etc. In this type of operation, the refuse is initially placed in a large refuse container which may be used as a storage bin for the refuse until the container becomes filled. The filled container is then emptied by a front end loader with the container being picked up by lifting arms and fork arms which engage the container to raise it above a storage body positioned on the refuse collection vehicle. After being raised above the refuse storage body, the container is inverted to dump its contents into the refuse storage body and the container is then returned to the ground. In picking up the container, the container is generally positioned forwardly of the refuse collection vehicle and is lifted over the cab of the vehicle to a position above the refuse storage body. The mode of operation of the refuse collection apparatus, with the refuse container positioned in front of the vehicle and being raised over the cab of the vehicle during pick-up, accounts for the name "front end loader."
Through use of a front end loader, the refuse, after being dumped into the storage body for the vehicle, is compacted through rearward movement of a compaction panel within the storage body. In its movement, the compaction panel is positioned forwardly of the opening into the refuse storage body for the vehicle. Then, after the deposit of refuse in the body through the opening, the panel is moved rearwardly to compact the refuse against a tailgate which is pivotally mounted on the storage body to close a rear opening in the storage body. After rearward movement of the compaction panel to pack the refuse, the panel is moved forwardly to pick up new refuse as it is dumped through the opening into the storage body, etc.
After a period of time, the refuse storage body for the collection vehicle will become filled with refuse. It is then necessary for the refuse collection vehicle to make a trip to a dumping point to unload the refuse. This is accomplished by moving the tailgate for the front end loader to a raised position and then ejecting the refuse from the refuse storage body by moving the panel rearwardly within the refuse storage body to push the refuse out of the rear opening.
The time required for unloading the refuse from the front end loader is lost time since the refuse collection apparatus merely performs as a truck during its trip to and from the dumping site. To reduce this lost time to a minimum, it is most desirable that the front end loader have a large capacity. The capacity of the front end loader could, for example, be increased simply through the expedient of making the refuse storage container larger. However, this is not a satisfactory solution since the size of a refuse collection vehicle may be dictated to a large extent by its ease in handling since the vehicle must be capable of picking up refuse containers behind office buildings and in alleys, etc. Thus, the only practical way to increase the capacity of the front end loader is to improve its efficiency such that it is able to compact refuse within the refuse storage body to a higher density with the storage body then being able to hold a larger quantity of refuse.
In the pick-up of refuse with a front end loader, a considerable amount of time is spent in moving the front end loader from one pick-up location to another. During these moves, when the front end loader is functioning as an over-the-road vehicle, the packing mechanism of present front end loaders is essentially inoperative. As described, the packing mechanism functions simply through rearward movement of a compaction panel within the refuse storage body with the panel then being moved forwardly after its rearward movement has been completed. Since the movement of the panel within the refuse storage body is relatively rapid, packing of the refuse may be completed within a relatively short time. Thus, when the front end loader is moved to a new pick-up location, the position of the panel within the storage body is generally fixed and the packing mechanism is not in operation.
During the pick-up of refuse by a front end loader, the refuse may be blown by the wind while being dumped from the inverted refuse container into the refuse storage body. This is very undesirable since it creates a source of litter at the refuse pick-up point. Additionally, when the refuse storage body is substantially full, refuse may extend upwardly through the opening in the storage body. This is also undesirable since the refuse can then be dislodged or blown from the storage body when the refuse collection vehicle is moved over the road to another location.
During the lifting of a loaded refuse container by a front end loader, it is most desirable that the position of the container be maintained reasonably horizontal. Otherwise, the container may be able to slide relative to the fork arms which support it which could result in dropping of the container. Also, during lifting of the refuse container, it is most desirable that some means be provided to prevent the container from being dropped if there should be a failure in the supplying of hydraulic fluid to the mechanism used in operating the lifting arms or the fork arms which engage the container.
During the packing of refuse within a refuse storage body, liquid will be dispelled from liquifiable items within the refuse such as vegetables, fruit, and other waste materials. The liquid which is formed may create problems through drainage from the refuse storage body. Thus, it would be most desirable to provide some means for retaining liquid within the refuse storage body such that the liquid does not drain from the storage body.
When the tailgate is in a lowered position relative to the refuse storage body, the tailgate must be locked, in some manner, to the storage body. This may create problems when it is desired to raise the tailgate to discharge refuse through the rear opening in the storage body. Thus, for example, it may be necessary to manually unlock the tailgate from the refuse storage body before moving of the tailgate to a raised position. This would be undesirable since it might require that the operator leave the vehicle cab to unlock the tailgate before actuating the mechanism to move the tailgate to a raised position. Also, by having the locking mechanism separate from the mechanism for lifting the tailgate, the tailgate might be inadvertently left unlocked after being moved to a lowered position in contact with the refuse storage body. This could create a safety hazard since the tailgate could then open when refuse within the storage body was moved rearwardly and packed against the tailgate. For these reasons, it would be desirable to have a locking mechanism for the tailgate which would function in combination with the mechanism for lifting of the tailgate. The operator would then not have to leave the vehicle cab to unlock the tailgate and there would be no possibility of inadvertently leaving the tailgate unlocked after moving the tailgate to a lowered position in engagement with the refuse storage body.
Another aspect of the invention concerns a refuse collection apparatus having a refuse storage body with a rear opening and a tailgate positioned adjacent the rear opening for movement between a raised position to expose the opening and a lowered position to close the opening. The tailgate has a lower member which is downwardly inclined in the direction of the storage body and the storage body has a contact surface adjacent the rear opening. The storage body has an inner bottom surface and the lower tailgate member and contact surface project below said bottom surface with the lower tailgate member and contact surface in contacting relation to form a liquid receiving well when the tailgate is in its lowered position. Sealing means are positioned between the downwardly inclined tailgate member and the downwardly projecting contact surface which form the liquid receiving well.